华北GPS网GAMIT计算结果与IGS站选取的关系探讨

利用GAMIT软件对1999年华北GPS网的观测数据进行了处理，在处理过程中，对IGS站的选取分为：（1）选取15个IGS站；（2）选取6个IGS站；（3）选取3个IGS站；（4）对不选IGS站的四种情况进行了计算，并对四种情况得出的结果从基线向量、测站坐标、基线的重复率和计算所得的均方根的残差nrms四个方面进行了比较，得出了以下结论：使用GAMIT软件处理GPS资料时，最好选取IGS站为区域网提供参考框架；IGS站的选取，数量上不一定最多，但空间分布上应尽量均匀；对华北GPS网，选取6个左右的IGS站即可；多期GPS资料在处理时应尽量选取相同的IGS站进行计算。

The Study of the Relationship Between the Result of GAMIT Processing and the Choice of IGS Station in the Northern China GPS Net

The observation data from Northern China GPS net has been processed using GAMIT soft-ware.In the processing,the choice of IGS station were divided into four cases:1.Choosing15IGS sta-tions;2.Choosing6IGS stations;3.Choosing3IGS stations;4.No IGS stations choosen.The results of the front four cases were compared form the repeat rate of baseline,baseline vector,site coordinates and the normalized root mean square(nrms).The conclusion is that it would be better choosing the reterence frame offered by IGS for the local net when processing GPS data with GAMIT software.The quantity might not be the most,but the choosen IGS stations should be well distributed in space as possible as they can.For the GPS net within1000Km,the best choice of IGS station is6also.The data of many times observation should use the same IGS stations to process as possible.